Most commonly, when you get a single click when attempting to start the engine, the starter solenoid or relay is faulty.
if its an electric start its probably in need of a new battery my xr 125 had the same problem and just had it changed and all is working fine hope that helps
The alternator might be the problem.
Charge your battery or tighten the battery cables.
You, in all probabilty have either bad battery connections, a bad battery or the start solenoid. I would say the connections are the problem.
Check your battery first, its terminal connection and connection leading to the starter.
battery or corroded connection on battery One click most likely is a bad starter motor or solenoid. Many clicks battery or connection problem.
Bad battery, starting motor or both.
Dead battery or a bad connection to the battery.
you need a new battery. if battery has been replaced and this still does not solve the problem, you must have had the bad battery for too long and it ruined the If the new battery doesn't solve the problem you can have check the battery cables, make sure they have a clean tight connection. Also the problem could be with your starter also.
If the battery is bad, you may only hear clicks. It could be the starter, but I would check the charge on the battery first.
Battery dead
A weak Battery